Vacuum cleaner

ABSTRACT

A cyclonic vacuum cleaner ( 10 ) comprises a separating unit ( 20 ) for separating dirt and dust from a dirt-laden airflow which is drawn in by the cleaner. The separating unit ( 20 ) has a chamber ( 205 ) with a collection area for collecting dirt and dust which is separated from the airflow. A base ( 210 ) of the separating unit ( 20 ) is movable between a closed position (FIG. 3) in which the closure member ( 210 ) seals the chamber and an open position by operation of a releasing means ( 220, 222, 230, 260 ). The releasing means is inhibited from releasing the base ( 210 ) when the unit ( 20 ) is stowed on the chassis ( 50 ) of the cleaner.

[0001] This invention relates to a vacuum cleaner which incorporates acollecting chamber.

[0002] Vacuum cleaners which separate dirt and dust from an airflowwithout the use of a filter bag, so-called bagless vacuum cleaners, arebecoming increasingly popular. Most bagless cleaners use cyclonic orcentrifugal separation to spin dirt and dust from the airflow. Byavoiding the use of a filter bag as the primary form of separation, ithas been found possible to maintain a consistently high level ofsuction, even as the collecting chamber fills with dirt.

[0003] The principle of cyclonic separation in domestic vacuum cleanersis described in a number of publications including EP 0 042 723. Ingeneral, an airflow in which dirt and dust is entrained enters a firstcyclonic separator via a tangential inlet which causes the airflow tofollow a spiral or helical path within a collection chamber so that thedirt and dust is separated from the airflow. Relatively clean air passesout of the chamber whilst the separated dirt and dust is collectedtherein. In some applications, and as described in EP 0 042 723, theairflow is then passed to a second cyclone separator which is capable ofseparating finer dirt and dust than the upstream cyclone. The airflow isthereby cleaned to a greater degree so that, by the time the airflowexits the cyclonic separating apparatus, the airflow is almostcompletely free of dirt and dust particles.

[0004] While bagless vacuum cleaners are successful in maintaining aconsistently high level of suction, the absence of a bag can make itdifficult to dispose of the dirt and dust which is collected by thecleaner. When the separating chamber of a bagless cleaner becomes full,a user typically removes the collecting chamber from the chassis of themachine, carries the chamber to a dust bin or refuse sack and tips thechamber upside down. Often dirt and dust is densely packed inside thecollecting chamber and it may be necessary for a user to manuallydislodge the dirt by reaching into the chamber and pulling at thecollected mass of dust and fibres, or to shake or bang the collectingchamber against the side of a dustbin. In some cases, this can cause afair amount of mess.

[0005] Some solutions to this problem have been proposed. U.S. Pat. No.5,090,976 describes the use of a disposable liner which can be fittedinside the cyclonic separating chamber. When the liner is full, theliner is lifted out of the chamber and disposed of WO 98/10691 describesa cyclonic collection chamber where a bag is retained, in a collapsedstate, in the base of the collection chamber. When the collectionchamber is full, the base is unscrewed from the chamber so that the bagcan extend downwardly from the base. Dirt and dust slides out of thecollecting chamber into the bag and the bag can then be sealed andseparated from the collecting chamber for disposal. Both of thesesolutions have a disadvantage in that they require a user to keep asupply of spare bases or liners, which adds to the cost of maintainingthe machine.

[0006] EP 1 023 864 describes a dust-collecting device for a cyclonicvacuum cleaner. The dust-collecting chamber can be removed from thechassis of the cleaner for emptying. A bottom lid of the dust-collectingchamber is attached by way of a hinge to the remainder of the chamberand the lid can be released by pressing a release button. A ribbedcylindrical filter is fitted inside the dust-collecting chamber and isrotatable within the chamber to encourage the release of dirt which isstored in the chamber.

[0007] The present invention seeks to provide a bagless vacuum cleanerwhich is more convenient for a user to manipulate.

[0008] Accordingly, the present invention provides a bagless vacuumcleaner comprising a collecting chamber which is removable from a stowedposition on a chassis of the vacuum cleaner, the collecting chambercomprising an inlet for receiving a dirt-laden airflow, an air outlet, acollection area for collecting, in use, dirt and dust which has beenseparated from the airflow and wherein part of the chamber wall in theregion of the collection area is a closure member which is movablebetween a closed position in which the closure member seals the chamberand an open position in which dirt and dust can escape from thecollection area, the chamber further comprising releasing means forreleasing the closure member from the closed position, and wherein thereleasing means are inhibited from releasing the closure member when theseparator is in the stowed position.

[0009] By inhibiting operation of the releasing means when thecollecting chamber is stowed on the chassis of the cleaner, it is notpossible for a user to accidentally release the closure member. Thisavoids the mess which would result if the cleaner were operated with theclosure member partially open or if the collecting chamber were removedfrom the chassis with the closure member partially open. Indeed, themanner in which the collecting chamber is supported on the chassis issuch that a user may not be aware that they had inadvertently releasedthe closure member until they removed the collecting chamber from thechassis.

[0010] The term ‘bagless’ is intended to cover a broad range of vacuumcleaners which have a reusable collecting chamber, and includes, interalia, cleaners which separate dirt and dust by way of cyclonic,centrifugal or inertial separation.

[0011] Preferably the closure member remains coupled to the collectingchamber, such as by a pivotal coupling. Thus, a user does not need tostruggle with refitting the closure member and there is no risk of theclosure member falling into a dust bin or refuse sack along with thedirt and dust which is released from the collecting chamber.

[0012] It is convenient for the actuating member to be located adjacenta handle for carrying the collecting chamber. This allows a user tocarry and empty the collecting chamber with one hand.

[0013] Preferably agitating means are provided for agitating dirt heldwithin the collection area, the agitating means being operable by thereleasing means. This helps to dislodge any dirt that may have become‘stuck’ in the collection area. Also, a user does not need to separatelyoperate the release and the agitating means.

[0014] Preferably the closure member is pivotably fixed to thecollecting chamber. However, it is also possible for the closure memberto be slideably movable with respect to the collecting chamber.

[0015] The collecting chamber preferably comprises a cyclonic separatorwhere dirt-laden air is spun at high speed to centrifugally separatedirt from the airflow but it can be any form of bagless separator wherethe collecting chamber is reused after it has been emptied.

[0016] The collecting chamber can have more than one separation stage.Preferably the collection areas of the first, second (and further) stageseparators each lie adjacent the closure member such that all of thecollected dirt and dust can be readily emptied from the collectingchamber.

[0017] Embodiments of the invention will now be described, by way ofexample only, with reference to the accompanying drawings in which:

[0018]FIG. 1 shows a bagless vacuum cleaner;

[0019]FIG. 2 shows just the dirt and dust separation unit of the vacuumcleaner of FIG. 1;

[0020]FIG. 3 is a cross-section along line A-A of the dirt and dustseparation unit of FIG. 2, with the base of the unit in a closedposition;

[0021]FIG. 4 shows the same cross-section as FIG. 3 but with the base ina partially open position;

[0022]FIG. 5 shows the same cross-section as FIG. 3 but with the base ina fully open position;

[0023]FIG. 6 is a cross-section through the dirt and dust separationunit mounted on the chassis of the vacuum cleaner;

[0024]FIG. 6A is a more detailed view of the same cross-section as FIG.6, showing the feature on the chassis which inhibits movement of thetrigger release mechanism;

[0025]FIG. 7 is a more detailed view of the lower part of thecross-section of FIG. 3; and,

[0026]FIG. 8 shows how dirt and dust accumulates in the dirt and dustseparation unit.

[0027] Referring to FIGS. 1 to 3, a vacuum cleaner 10 has a main chassis50 which supports dirt and dust separation apparatus 20. The lower partof the cleaner 10 comprises a cleaner head 22 for engaging with thefloor surface. The cleaner head has a downwardly facing suction inletand a brush bar is mounted in the mouth of the inlet for agitating thefloor surface. The cleaner head is pivotably mounted to a motor housing24 which houses the motor and fan of the cleaner. Support wheels 26 aremounted to the motor housing for supporting the cleaner and allowingmovement across a floor surface. A spine of the chassis 50 extendsupwardly from the motor housing 24 to provide support for the componentsof the cleaner. A cleaning wand 42 having a second dirty air inlet 43 isconnected by way of a hose (not shown) to the chassis at the base of thespine 50. The wand 42 is releasable from the spine 50 so as to allow auser to carry out above-the-floor cleaning and cleaning in places whichare inaccessible by the main cleaning head 22. When the wand is fixed tothe spine 50, the wand 42 forms the handle of the cleaner and a handgrip40 at the remote end of the wand 42 allows a user to manoeuvre thecleaner. These features of the cleaner are well known and have been welldocumented elsewhere and can be seen, for example, in cleaners which aremanufactured by DYSON™, and thus will not be described in any furtherdetail.

[0028] Dirty air from the cleaner head 22 or wand inlet 43 is carried tothe separator unit 20 by inlet conduit 28 and inlet 30. Separator 20 isa cyclonic separator which spins dirt, dust and other debris out of theairflow by centrifugal separation. One particular form of separator unit20 is shown in detail in the figures as a preferred embodiment but itshould be understood that there are many other ways in which theseparator could be constructed. In the illustrated separator unit 20,airflow passes through a first separation stage and then a secondseparation stage. The first separation stage is a substantiallycylindrically-walled cyclonic chamber 205 whose purpose is to separatelarge debris and dirt from the airflow. Inlet 30 is arranged to directdirty air into the chamber 205 in a tangential direction to the wall ofthe chamber. Fins or baffles 207 extend radially outwardly from acentral core of the chamber and serve to discourage separated dirt ordust from becoming re-entrained in the airflow when the vacuum cleaneris first started. The outlet of the first separation stage is a shroud260, i.e. an apertured annular wall mounted coaxially inside the chamber205. The area on the inner side of the shroud leads to the secondseparation stage. The second separation stage is a set of taperedcyclonic chambers 240 which are arranged in parallel with one another.Each cyclonic chamber 240 has a tangential inlet 242, an outlet 243 forseparated dirt and dust and a cleaned air outlet 244. Each of thecleaned air outlets 244 of the cyclonic chambers 240 communicate with anoutlet conduit such that air from the individual outlets of the parallelcyclonic chambers is recombined into a single flow. The outlet conduitmates with a port on the chassis spine 50 when the separator unit 20 isfitted to the chassis.

[0029] In use dirty air which is laden with dirt, dust and other debrisenters the first separation stage via inlet 30 and follows a spiral patharound the chamber 205. The centrifugal force acting on the material inthe airflow causes the larger debris and dirt to be separated from theairflow. This separated material collects at the base of the chamber205, against base 210, due to a combination of gravity and the pressuregradient which exists in chamber 205 while the cleaner is in operation.The airflow passes through the shroud 260. The shroud 260 causes air toperform a sharp change of direction and causes fibrous material tocollect on the outer wall of the shroud 260. The airflow passes to thesecond separation stage where it is divided between the cyclonicchambers. Air enters a respective one of the chambers via a tangentialinlet and is then constrained to follow a spiral path of decreasingradius which greatly increases the speed of the airflow. The speed issufficient to separate dirt and extremely fine dust from the airflow.The separated dirt and dust exits the cyclonic chambers 240 via outlets243 which communicate with a central conduit 245. Dirt and dust falls,under gravity, towards the base of conduit 245 and collects at the lowerend of the conduit 245 adjacent the base 210 in region 270 (FIG. 8).Cleaned air from the parallel chambers 245 is recombined into a singleflow and is channelled out of the separator unit 20, down the spine 50of the chassis and through a pre-motor filter, fan and post-motor filterbefore finally being exhausted from the cleaner.

[0030] It should be understood that the second separation stage need notbe a set of parallel cyclonic chambers 240. The second separation stagecould be a single tapered cyclonic chamber which can fit inside thecylindrical chamber of the first separation stage, as shown in EP 0 042723. Alternatively, the second separation stage could be a furthercylindrical cyclone or it could be omitted altogether. The firstseparation stage may be a tapered chamber rather than the cylindricalone described. However, in each of these alternatives, dirt and dustwill be separated from an airflow without the use of a filter bag andwill collect in a collection area.

[0031] The separator unit 20 is supported by the chassis 50 and isreleasably held upon the chassis by a catch 280, shown more clearly inFIG. 6A. The separator unit 20 is shown by itself in FIGS. 2-5. Theseparator unit 20 is releasable from the chassis to allow the separatorto be emptied. A handle 202 is provided at the top of the separator unit20 for allowing a user to carry the unit 20. The base 210 of theseparator unit is movable between a closed position (shown in FIGS. 2,3) and an open position (shown partially open in FIG. 4 and fully openin FIG. 5) to permit emptying of the unit 20. The base 210 is hinged 214to the cyclone chamber 205 to allow pivotal movement between the base210 and chamber 205. Two separate collection areas lie adjacent to thebase 210. The first collection area is the annular region between thecylindrical chamber wall 205 and the inner wall 206 at the lower end ofthe separator. The second collection area 270 is the area within thetube-like part 206. Thus, when base 210 opens, material empties fromboth of the collection areas. The outer annular edge of the base 210 hasa radially inwardly extending slot to hold a seal 212. In use, with thebase closed, the seal 212 fits tightly against the inner wall of thechamber 205 to maintain an air and dust-tight seal. A second seal 213extends axially outwardly from the lower annular edge of part 206 suchthat it fits tightly against the axially extending wall of the raisedcentral cap of the base 210. Seals could be located in other positionsto achieve the same sealing effect of the base. The base 210 is held inthe closed position by a lock mechanism 260, 262. The locking mechanismis controlled by a manually operable trigger 220. A linking mechanism222, 223, 224, 230 joins the trigger 220 to the lock mechanism. Trigger220 is received in a vertically extending channel on the spine-facingside of the separator which confines the trigger to follow a verticalmovement. A lug on the trigger cooperates with a lever arm 222. Thelever is pivotably fixed to the housing such that the remote end of thelever arm pushes downwardly against the upper end 231 of push rod 230.The push rod 230 is resiliently biased by spring 223 in the positionshown in FIG. 3 and can be displaced downwardly (to the position shownin FIG. 4) against the action of the spring 223 when the trigger ispulled. Spring 223 is held in a cavity of the housing and respectiveends of the spring 223 act against the end wall of the cavity and theflange which is carried by the push rod 230 near end 231. The linkingmechanism is shielded from dust by a gaiter 224, which is attached tothe push rod 230 and the housing of the separator unit. The gaiter 224stretches as the push rod moves downwardly, maintaining a dust-tightshield for the mechanism behind the gaiter 224.

[0032] The lowermost end of the push rod has an inclined face whichcooperates with a similarly inclined face on the catch 260 at the base.Catch 260 is pivotably mounted to the base and can be displaced, againstthe bias of spring 262, to the position shown in FIG. 4. The catch has ahook 263 which engages with a corresponding hooked feature 264 on thecentral part of the base 210 so as to hold the base 210 in the closedposition. The lowermost surface of the catch 260 is curved such thatwhen the base 210 is pushed towards the closed position the catch 260 isdisplaced, allowing the hook 264 on the base 210 to engage with the hook263 on the catch 260.

[0033] It will be appreciated that the trigger, linking mechanism andlock can be realised in many alternative ways. For example, the trigger220 could be linked directly to the push rod 230, rather than beingindirectly linked by the lever 222.

[0034] The lower end of the push rod 230 also carries an agitator 250.The agitator 250 is fixed to the push rod and thus moves upwardly anddownwardly with the push rod as the trigger 220 is operated. In use, aplug of dirt and dust may form at the lower end of the second collectionarea, next to base 210. The agitator 250 has radially outwardlyextending fins. In use, movement of the agitator will either push theplug or break the plug into smaller parts which can then fall out of thecollection area. The inner surfaces of the collection tube are smoothand tapered to discourage dirt from settling. The agitator could be moreelaborate than the one shown here. For example, the agitator could bearranged to rotate about the longitudinal axis of the push rod 230 asthe push rod moves upwards or downwards. A second agitator could beprovided in the first collection area, the second agitator also beinglinked to the push rod or release mechanism. The cutting effect of theagitator on a plug of material can be improved by forming sharp orpointed edges on the agitator.

[0035] To ensure an air and dust-tight seal around the base, the seal212 fits tightly against the chamber. This may cause the base to ‘stick’in the closed position when the catch 260 is released. The push rod 230has a sufficient length such that, when it is operated, it movesdownwardly towards the catch 260, operates catch 260 and then continuesto move towards the base 210, pushing against the base, overcoming theresistance of the seal 212 against the chamber wall 205 and thus pushingthe base 210 open.

[0036] In use, a user removes the separator unit 20 from the chassis byoperating release member 280 and carries the separator unit 20, by wayof handle 202, to a dust bin or refuse sack. The lower end of theseparator unit is held over or within the dust bin or sack and thetrigger 220 is pulled. This causes the base 210 to swing open and dirt,dust and debris which has been collected in the chamber 205 falls out ofthe unit 20 into the bin. Due to the distance between the handle andbase, and the direction in which the dirt falls from the unit 20, a useris not brought into contact with the dirt. As the dirt collects againstthe part of the chamber which opens, i.e. base 210, the dirt falls outof the chamber 205 with little or no additional effort by a user. Finedust collected within the second stage collector 270 can be fullycleared by the user operating trigger 220 several times. This willoperate agitator 250.

[0037]FIG. 6 shows the separator unit 20 in position on the chassis 50of the cleaner 10. To ensure that the base 210 is not accidentallyopened when the cleaner is in use, the chassis 50 has a projection 218which fits inside a notch 217 on the trigger 220 when the separator unit20 is fitted to the chassis 50. Thus, the trigger 220 is inhibited frommoving in the vertical direction which is necessary for the closuremember 210 to be released.

[0038] In the arrangement shown in the drawings the base 210 ispivotably fixed to the chamber. It would also be possible for the baseto be slideable with respect to the chamber.

1. A bagless vacuum cleaner comprising a chassis and a collectingchamber which is removable from a stowed position on the chassis, thecollecting chamber comprising an inlet for receiving a dirt-ladenairflow, an air outlet, a collection area for collecting, in use, dirtand dust which has been separated from the airflow and wherein pan ofthe chamber wall in the region of the collection area is a closuremember which is pivotably attached to the chamber and is movable betweena closed position in which the closure member seals the chamber and anopen position in which dirt and dust can escape from the collectionarea, the chamber further comprising releasing means capable ofoperating so as to allow the closure member to move from the closedposition to the open position and wherein the releasing means areinhibited from operating in said manner when the collecting chamber isin the stowed position.
 2. A vacuum cleaner according to claim 1 whereinthe chassis of the vacuum cleaner has a projection for locating in arecess on the releasing means of the collecting chamber and forinhibiting movement of the releasing means.
 3. A vacuum cleaneraccording to claim 1 or 2 wherein the releasing means is operable toapply an opening force to the closure member.
 4. A vacuum cleaneraccording to claim 3 wherein the releasing means is operable to apply anopening force to the closure member at a position which is spaced fromthe pivot.
 5. A vacuum cleaner according to any one of the precedingclaims wherein the releasing means comprises an actuating member and alinking mechanism which couples the actuating member to the closuremember.
 6. A vacuum cleaner according to claim 5 further comprisingagitating means for agitating dirt held within the collection area, theagitating means being operable by the actuating member.
 7. A vacuumcleaner according to claim 6 wherein the agitating means is mounted onthe linking mechanism.
 8. A vacuum cleaner according to any one ofclaims 5 to 7 wherein the actuating member is located at an opposite endof the collecting chamber to where the closure member is located.
 9. Avacuum cleaner according to any one of claims 5 to 8 further comprisinga handle for carrying the collecting chamber and wherein the actuatingmember is located adjacent the handle.
 10. A vacuum cleaner according toclaim 9 wherein the actuating member is a trigger mechanism which islocated beneath the handle.
 11. A vacuum cleaner according to any one ofthe preceding claims wherein the closure member is lockable in theclosed position.
 12. A vacuum cleaner according to claim 11 wherein theclosure member is automatically locked as the closure member is movedtowards the closed position.
 13. A vacuum cleaner according to claim 12wherein the lock is resiliently mounted such that it can be temporarilydisplaced by the closure member as the closure member is moved towardsthe closed position.
 14. A vacuum cleaner according to any one of thepreceding claims wherein the closure member is pivotably fixed to thecollecting chamber.
 15. A vacuum cleaner according to any one of claims1 to 13 wherein the closure member is slideably movable with respect tothe collecting chamber.
 16. A vacuum cleaner according to any one of thepreceding claims wherein the closure member carries a seal for sealingagainst the part of the collection area in which it is fitted.
 17. Avacuum cleaner according to any one of the preceding claims wherein theclosure member forms a surface against which dirt and dust can collectduring operation of the vacuum cleaner.
 18. A vacuum cleaner accordingto claim 17 wherein the closure member forms a base of the collectingchamber.
 19. A vacuum cleaner according to any one of the precedingclaims wherein the collecting chamber comprises a cyclonic separator.20. A vacuum cleaner according to claim 19 further comprising a secondstage separator and a second stage collection area, and wherein both thesecond stage and first stage collection areas lie adjacent the closuremember.
 21. A vacuum cleaner according to claim 20 wherein the secondstage collection area lies within the first stage collection area.
 22. Avacuum cleaner according to claim 21 further comprising a wall whichseparates the second stage collection area from the first stagecollection area.
 23. A vacuum cleaner substantially as described hereinwith reference to the accompanying drawings.